Node.js in Action

417 Pages·2014·6.78 MB·English

by  Mike Cantelon

Mike Cantelon
Marc Harter
T.J. Holowaychuk
Nathan Rajlich

FOREWORD BY Isaac Z. Schlueter
M A N N I N G
Node.js in Action
MIKE CANTELON
MARC HARTER
T.J. HOLOWAYCHUK
NATHAN RAJLICH
MANNING
SHELTER ISLAND
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ISBN 9781617290572
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1 2 3 4 5 6 7 8 9 10 – MAL – 18 17 16 15 14 13
brief contents
PART 1 NODE FUNDAMENTALS...................................................1
1 ■ Welcome to Node.js 3
2 ■ Building a multiroom chat application 14
3 ■ Node programming fundamentals 37
PART 2 WEB APPLICATION DEVELOPMENT WITH NODE.............69
4 ■ Building Node web applications 71
5 ■ Storing Node application data 97
6 ■ Connect 123
7 ■ Connect’s built-in middleware 145
8 ■ Express 176
9 ■ Advanced Express 202
10 ■ Testing Node applications 242
11 ■ Web application templating 264
PART 3 GOING FURTHER WITH NODE....................................293
12 ■ Deploying Node applications and maintaining uptime 295
13 ■ Beyond web servers 309
14 ■ The Node ecosystem 343
iii

contents
foreword xiii
preface xv
acknowledgments xvi
about this book xviii
about the cover illustration xx
PART 1 NODE FUNDAMENTALS..........................................1
1 Welcome to Node.js 3
1.1 Built on JavaScript 4
1.2 Asynchronous and evented: the browser 5
1.3 Asynchronous and evented: the server 7
1.4 DIRTy applications 8
1.5 DIRTy by default 10
Simple async example 11 ■ Hello World HTTP server 12
Streaming data 12
1.6 Summary 13
2 Building a multiroom chat application 14
2.1 Application overview 15
2.2 Application requirements and initial setup 17
Serving HTTP and WebSocket 17 ■ Creating the application
file structure 18 ■ Specifying dependencies 19 ■ Installing
dependencies 19
v
vi CONTENTS
2.3 Serving the application’s HTML, CSS, and client-side
JavaScript 20
Creating a basic static file server 20 ■ Adding the HTML and CSS
files 23
2.4 Handling chat-related messaging using Socket.IO 25
Setting up the Socket.IO server 26 ■ Handling application
scenarios and events 27
2.5 Using client-side JavaScript for the application’s user
interface 31
Relaying messages and name/room changes to the server 32
Showing messages and available rooms in the user interface 33
2.6 Summary 36
3 Node programming fundamentals 37
3.1 Organizing and reusing Node functionality 38
Creating modules 40 ■ Fine-tuning module creation using
module.exports 42 ■ Reusing modules using the node_modules
folder 43 ■ Caveats 44
3.2 Asynchronous programming techniques 46
Handling one-off events with callbacks 46 ■ Handling repeating
events with event emitters 50 ■ Challenges with asynchronous
development 57
3.3 Sequencing asynchronous logic 58
When to use serial flow control 59 ■ Implementing serial flow
control 61 ■ Implementing parallel flow control 63
Leveraging community tools 65
3.4 Summary 67
PART 2 WEB APPLICATION DEVELOPMENT WITH NODE ....69
4 Building Node web applications 71
4.1 HTTP server fundamentals 72
How Node presents incoming HTTP requests to developers 73
A basic HTTP server that responds with “Hello World” 74
Reading request headers and setting response headers 75
Setting the status code of an HTTP response 75
CONTENTS vii
4.2 Building a RESTful web service 76
Creating resources with POST requests 77 ■ Fetching resources
with GET requests 79 ■ Removing resources with DELETE
requests 80
4.3 Serving static files 81
Creating a static file server 82 ■ Handling server errors 85
Preemptive error handling with fs.stat 86
4.4 Accepting user input from forms 87
Handling submitted form fields 87 ■ Handling uploaded files
using formidable 90 ■ Calculating upload progress 94
4.5 Securing your application with HTTPS 94
4.6 Summary 96
5 Storing Node application data 97
5.1 Serverless data storage 98
In-memory storage 98 ■ File-based storage 99
5.2 Relational database management systems 102
MySQL 102 ■ PostgreSQL 110
5.3 NoSQL databases 112
Redis 112 ■ MongoDB 117 ■ Mongoose 119
5.4 Summary 121
6 Connect 123
6.1 Setting up a Connect application 124
6.2 How Connect middleware works 125
Middleware that does logging 126 ■ Middleware that responds
with “hello world” 126
6.3 Why middleware ordering matters 127
When middleware doesn’t call next() 128 ■ Using middleware
order to perform authentication 128
6.4 Mounting middleware and servers 129
Middleware that does authentication 130 ■ A middleware
component that presents an administration panel 131
viii CONTENTS
6.5 Creating configurable middleware 133
Creating a configurable logger middleware component 133
Building a routing middleware component 135
Building a middleware component to rewrite URLs 137
6.6 Using error-handling middleware 138
Connect’s default error handler 139 ■ Handing application errors
yourself 139 ■ Using multiple error-handling middleware
components 141
6.7 Summary 144
7 Connect’s built-in middleware 145
7.1 Middleware for parsing cookies, request bodies,
and query strings 146
cookieParser(): parsing HTTP cookies 147 ■ bodyParser():
parsing request bodies 150 ■ limit(): request body limiting 151
query(): query-string parser 153
7.2 Middleware that implements core web application
functions 154
logger(): logging requests 155 ■ favicon(): serving a
favicon 157 ■ methodOverride(): faking HTTP methods 158
vhost(): virtual hosting 160 ■ session(): session
management 161
7.3 Middleware that handles web application security 165
basicAuth(): HTTP Basic authentication 165 ■ csrf(): cross-site
request forgery protection 167 ■ errorHandler(): development error
handling 168
7.4 Middleware for serving static files 170
static(): static file serving 170 ■ compress(): compressing static
files 172 ■ directory(): directory listings 174
7.5 Summary 175
8 Express 176
8.1 Generating the application skeleton 178
Installing the Express executable 180 ■ Generating the
application 180 ■ Exploring the application 180
8.2 Configuring Express and your application 183
Environment-based configuration 183
CONTENTS ix
8.3 Rendering views 185
View system configuration 185 ■ View lookup 188 ■ Exposing
data to views 189
8.4 Handling forms and file uploads 194
Implementing the photo model 194 ■ Creating a photo upload
form 194 ■ Showing a list of uploaded photos 197
8.5 Handling resource downloads 198
Creating the photo download route 198 ■ Implementing the photo
download route 199
8.6 Summary 201
9 Advanced Express 202
9.1 Authenticating users 203
Saving and loading users 204 ■ Registering new users 209
Logging in registered users 214 ■ User-loading middleware 217
9.2 Advanced routing techniques 219
Validating user content submission 219 ■ Route-specific
middleware 223 ■ Implementing pagination 225
9.3 Creating a public REST API 229
Designing the API 229 ■ Adding Basic authentication 229
Implementing routing 230 ■ Enabling content negotiation 234
9.4 Error handling 236
Handling 404 errors 236 ■ Handling errors 238
9.5 Summary 241
10 Testing Node applications 242
10.1 Unit testing 243
The assert module 244 ■ Nodeunit 247 ■ Mocha 249
Vows 254 ■ Should.js 256
10.2 Acceptance testing 258
Tobi 259 ■ Soda 260
10.3 Summary 262
11 Web application templating 264
11.1 Using templating to keep code clean 265
Templating in action 266